Auto-oxidation and polymerization



Patented 3, 1936 UNITED STATES 2,032,554 AUTO-OXIDATION POLYMERIZATIOH CATALYST Franciscus Vissert Hooi't, Buflalo, N. Y., assignor to Lucidol Corporation, Buflalo, N. Y., a corporation of Delaware No Drawing. Application August 3, 1933,

Serial No. 683,544

Claims.

The present invention relates to a new auto-.

oxidation and polymerization catalyst and to methods of employing the same in various processes including the drying of those drying oils which contain elaeostearin. More particularly the present invention relates to organic peroxides properly so-called, and their use in such drying oils as China-wood oil and similar oils, which consist largely of elaeostearin. As is well known, tung oil (or China-wood oil) oiaverage quality contains about 85% of elaeostearin.

The drying of so-called drying oils is a complicated process in which polymerizations are accompanied, preceded or followed by oxidations.

. According to Eibner (Das Oeltrocknen, 1930) drying of oils is due to autoeoxidation and polymerization. In the case 'of raw linseed oil, Eibner states that drying is due to auto-oxidation, in raw China-wood oil to auto-oxidation and polymerization. In bodied oils, that is oils of which the viscosity has been increased, a certain polymerization occurs during the bodying process. The drying process of bodied oils involves the formation of films from partly polymerized products under the influence of'auto-oxidation.

It was old prior to the present --invention to use (with all typesof drying oils) oil drying agents such as metal oxides, metal soaps, metal resinates, and the like to accelerate the drying under atmospheric conditions. The use of these driers has various disadvantages in that they unfavorably afiect the stability of the oil films pro duced by the drying of the oil, causing a tendency to wrinkle, also checking and cracking of the' films, decreasing the water resistance of the films,

decreasing the life of the films and other highly undesirable effects. The reason for most of these unfavorable eflects caused by the driers is the fact that they catalyze for the most part, the auto-oxidation of the drying oils, without appreciably accelerating the polymerization.

It was alsoknown prior to the present inven accelerate drying of the oil contained in a print= ing ink by heating the ink containing the rubrene peroxide distributed throughout the mass there- .of (see U. S. Patent 1,842,196) However the. term rubrene peroxide" is now generally considered to be a misnomer and themost recent investigations indicate that it is an oxidecapable of dissociation into rubrene' and Oxygen, andlnot possessing the characteristic properties of a true peroxide, These comments are pertinent as will appear more fully hereinafter, because I employ a true organic diacyl peroxide, such as dibenzoyl peroxide, in effecting an acceleration of the drying of an oil of 5 the China-wood oil type. These diacyl peroxides, as distinguished from rubrene peroxide, are not capable of dissociation to liberate free oxygen by heating.

I have now'found that drying oils of the type of 10 China-Wood oil, i. 6., oils containing elaeostearin, can be dried under atmospheric conditions with out the use of any of the above mentioned or any other commercial driers, by the addition of diacyl peroxides to the oils. These diacyl peroxides are catalysts which accelerate the natural rate of drying of the oils. They do not considerably accelerate the drying of oils of the type of linseed oil. The mechanism of the drying operation of oils of the type of linseed oil involves auto-oxidation. Only in the case of drying oils of the type of China-Wood'oil where both auto-oxidation and polymerization are involved, the diacyl peroxides accelerate the rate of drying, to any commercially useful extent.

While dibenzoyl peroxide and other organic peroxides have been used heretofore to bleach oils, no one prior to the present invention realized the potentiality of these peroxides as specific drying accelerators for oils of the type of China-wood Example I A quick drying paint is produced by mixing the following materials and grinding them in a paint mill, for example a pebblemill:

y Pounds Zinc oxide -i l -25o Bodied China-wood oil'. 250 Mineral spirits 70 Powdered dibenzoyl peroxide 2.8

This paint, when brushed onto a board, will dry in the airin 4-5 hours, when poured on glass in 7-8 hours, while a similar paint made with the same ingredients but without dibenzoyl peroxide (CsHsCO) 202 will still be wet on the board t in 6 hours and on the glass even after 48 hours. m

' This hot plate test consists in smearing some oi -tion and polymcrizatiom occurs.

'hibitors may counteract this effect of the diacyl peroxides, but usually the inhibitors react chemicallymith the diaoyl peroxides, thereby slowly'.

the ink upon a glass plate which is maintained at 100 0., and noting the time when the ink has dried sufliciently so that it will not smear when touched by the operator with a cleanfinger.

' These diacyl peroxides can'be used as ingredients in regular stock inks containing China-wood oil but their action on the elaeostearin is so pronounced that under ordinary storage conditions, even after a'short time, fskinning and flivering" oi the inks caused by premature oxida Certain in-.

converting the-peroxides into non-accelerators and the useful eii'ect of the peroxides is thereby lost.

The particular ink 01' ExampleII, containing I a-inhibitor, must be used imnlediately, and cannot- -be left even iora .i'ew days without. livering.

Example. III

quick drying raw China-wood oil is pre-' pared by adding 6 ounces of dimyristoyl peroxide (Ci3H2'lCo)202 til, 100 pounds 01' raw China-wood oil and stirring the oil at room all the peroxide is dissolved.

While an untreated oil'gave a drying test of 18 hours, the treated oil dried under the same con-' a ps rv Afqdick drying bodied oil is .producedb'yr'addingflt ounces 01' mm ditoluvl peroxide (CHQC6H4CO)2Q2 to 100 pounds 01' bodied China-wood oilt'andstirring-the oil at 40-60! 0;-

untilthe peroxide has dissolved. Such a treated oil will dry in 4 hours against adrying time of hoursior. the

untreated bodied oil. I Example .7 An example oi'a rapid drying varnish contain ing a diacyl peroxide is prepared as follows: To

100 pounds ofany v arnish gum and 250 pounds. of mag oil properly cooked and thinned with 100 pounds 01 mineral spirits, and 1 pound'oi pp ditoluyl peroxide (CHhCsI-RCO)20:. The b ve varnish dried hard'in seven hours, while the same varnishomitting pp ditoluyl peroxide re. 'quired 23hours to dry under the same condiv tions.

' The diacyl peroxides disclosedthe above examples are t'rue organic peroxides or derivatives ofhydrogen peroxide and possess the characteristic oxygen bridge-'-O--O. 'Diacyl peroxides z are derived from H2O: by: repl'acelnentoi the I two hydrogen atoms by one or t'wo acyl groups.

- The best known 'diacyl peroxide is dibenz'oyl persubject to a dissociation or reversible oxidation.

[75 Oxide molecule is oxide ((3133.00) 20:. These diacyl peroxides diti'rirom rubrene-pe'roxide" in that they do not liberate free oxygen when heated and are not But one oi the oxygen atoms of the'diacyfperactive' 1. e. seems. to fun tion temperature untii E as a powerful catalyst, and is quite diiierent chemically and acts differently .irom the tree oxygen which is liberated from substances such as rubrene peroxide. Forthe purpose of clar-' ity and simplification oi the explanation of the invention, the per cent of diacyl peroxide used with the oil to' polymerize the same and also the per cent 01' factlve oxygen" with reference to the said oils are tabulated below, the second table being based on the speciflcfexamples, each item identifying the particular example on which The following table also gives the amount 01 diacyl peroxide in percentage ofoil as used in the live examples given in the patent application. I

. In this same table we also calculated the active oxygen in percentages of oils The spplicati tion is notlimited The diacyl peroxides'act in'a wholly unexpected manner as catalysts for the on I .H a 1' oils of the type of china wood 011, containing elaeostearin. Its appar nt action is on' compounds with the triple ooniusated system:

' --cn=cnl-cn =clr--cnf=cn*-.

lamented amnesty heat; falls or oxygen or by a combination or these. At or:

dinaryroomtemperatureandindiduseddaylightvthere is a distinct accelerat wfla nmduoed peroxideswhich causes of the principle of niy in'yen however by the diacyl faster vltlry'ins 0! oil.

tothe above examples; Other applications oi the catalytic action of diacyl peroxides on oils of the type 01 China-wood oil will be obvious, such as impregnating pulp, paper and woven. fabrics, etc'. Forexample, an oil-proof cohtainer made by a cont'aina.

constructedi'rom paper, wood pulp or cardboard with tung oil and a small amount-of a diacyl peroxide and hardening the-tung" .oilin the walls of the thusimpregnated container. The oil used in these applications does notnece aarily have to Diactyl peroxide peef F g? on oil.

Exam lo 1- 250 go (is oil Per cent .Per mu 2.3poundsbensoyl peroxide 0.92 0.0610 Example 2-! 100 oi] 5.5 pounds dilauroyl peroxide 5. 5 0. 2211. xample 3- 100 pounds oil v ii ounces dimyristayl peroxide 0. 316 0.0a: xam e 4- v I 100 pounds oil 3% ounces mm ditoluyl peroxide 0. 219 0. 090 Example 6- 250 pounds tang oil i 1 pound pp'ditoluyl peroxide 0. 4 0.02%!

be all oi'the type oi China-woo'd oil, because ex celler t drying results can be obtained on mixt of China-'woodoil withother-oils ii only care has beentaken to have a suflicient proportion oi China-wood bil present so that the desired drying eflect is obtained by the action of the diacyl peroxide .on'. the elaebstearin present. It is also clear that various combinations and mixtures of aosasss the reaction products of such materials, which substance are well known to be "reactive to and injurious to the ordinary heavy metal driers which have heretofore been extensively used in coating compositions containing drying oils, and which interfere with the drying 01' such coating compositions.

By the term paint"- I mean a composition which is oi such a fluid consistency that it can be applied to surfaces by means or a brush dipped into the said paint. The ratio of liquid vehicle to pigment is high, so that the entire paint would be considered as a liquid mass. By the term "printing ink I mean compositions having the composition of a relatively stifi paste. In speakv ing of quick drying paint", I mean that the paint will dry on a glass surface, in substantially less than 48 hours, and in speaking of quick drying" printing ink, I mean that the printed sheet can be overlaid with another printed sheet, within some seconds, or at any event a few min-.

'utes after the printing operation, without smutting, and without the need of using smut sheets. Varnishes are analogous to paints", in that they can be applied as a liquid.

What I claim is:

1. A quick drying coating composition for application to a non-reactive material, which composition contains as a part at least oi the vehicle, a bodied drying oil of the type consisting largely of elaeostearin, said composition containing a major traction of one percent by weight of dibenzoyl peroxide, based on said drying oil, functioning'as the essential oxidation and polymerization catalyst, for the elaeostearin.

2. A quick drying coating composition for application to a non-reactive material, which composition contains a bodied drying oil of the type consisting largely of elaeostearin, said composl tion beir" substantially free from heavy metal drier compounds, and containing active oxygen in amount equal to about 0.01% to 025% by weight of the said oil, said active oxygen being in the form of a diacyl peroxide, said peroxide functioning as the essential oxidation and polymerization catalyst.

3. A quick drying bodied China-wood 011 com-- position containing a diacyl peroxide dissolved in bodied China-wood 011, said peroxide providing about 0.01 to 0.25% of active oxygen, based on the amount oi! said oil, which composition will dry .in about four hours.

4. A quick drying varnish containing a bodied drying oil consisting largely of elaeostearin as the essential drying oil, and containing not substantially over 0.25% active oxygen based on the said drying oil content, in the form. of a diacyl 'peroxide as the essential oxidation and'polymerization'catalyst, and which varnish will dry hard in .not substantially over seven hours.

5. A quick drying brushable paint which oontains a bodied drying oil 01 the type consisting largely oi elaeostearin as the essential drying oil, and a diacyl peroxide as the essential oxidation and polymerization catalyst, the amount of said peroxide corresponding to about 0.01% to 0.25%

of active oxygen, based on the amount of said oil, and which paint, when spread upon a board will dry in the air, in not substantially over 5 hours.

FRANCISCUS VISSERT HOOFT. 

